Graphical user interface for a display screen or portion thereof



FIG. 1 is a front view of a graphical user interface for a display screen or portion thereof showing my new design;

FIG. 2 is a front view of a second embodiment thereof;

FIG. 3 is a front view of a third embodiment thereof; and,

FIG. 4 is a front view of a fourth embodiment thereof.

The broken lines showing a display screen or portion thereof and other elements in all the figures form no part of the claimed design. 

The ornamental design for graphical user interface for a display screen or portion thereof, as shown and described. 